include/asm-powerpc/dma-mapping.h

   1 /*
   2  * Copyright (C) 2004 IBM
   3  *
   4  * Implements the generic device dma API for powerpc.
   5  * the pci and vio busses
   6  */
   7 #ifndef _ASM_DMA_MAPPING_H
   8 #define _ASM_DMA_MAPPING_H
   9 #ifdef __KERNEL__
  10
  11 #include <linux/types.h>
  12 #include <linux/cache.h>
  13 /* need struct page definitions */
  14 #include <linux/mm.h>
  15 #include <linux/scatterlist.h>
  16 #include <asm/io.h>
  17
  18 #define DMA_ERROR_CODE          (~(dma_addr_t)0x0)
  19
  20 #ifdef CONFIG_NOT_COHERENT_CACHE
  21 /*
  22  * DMA-consistent mapping functions for PowerPCs that don't support
  23  * cache snooping.  These allocate/free a region of uncached mapped
  24  * memory space for use with DMA devices.  Alternatively, you could
  25  * allocate the space "normally" and use the cache management functions
  26  * to ensure it is consistent.
  27  */
  28 extern void *__dma_alloc_coherent(size_t size, dma_addr_t *handle, gfp_t gfp);
  29 extern void __dma_free_coherent(size_t size, void *vaddr);
  30 extern void __dma_sync(void *vaddr, size_t size, int direction);
  31 extern void __dma_sync_page(struct page *page, unsigned long offset,
  32                                  size_t size, int direction);
  33
  34 #else /* ! CONFIG_NOT_COHERENT_CACHE */
  35 /*
  36  * Cache coherent cores.
  37  */
  38
  39 #define __dma_alloc_coherent(gfp, size, handle) NULL
  40 #define __dma_free_coherent(size, addr)         ((void)0)
  41 #define __dma_sync(addr, size, rw)              ((void)0)
  42 #define __dma_sync_page(pg, off, sz, rw)        ((void)0)
  43
  44 #endif /* ! CONFIG_NOT_COHERENT_CACHE */
  45
  46 #ifdef CONFIG_PPC64
  47 /*
  48  * DMA operations are abstracted for G5 vs. i/pSeries, PCI vs. VIO
  49  */
  50 struct dma_mapping_ops {
  51         void *          (*alloc_coherent)(struct device *dev, size_t size,
  52                                 dma_addr_t *dma_handle, gfp_t flag);
  53         void            (*free_coherent)(struct device *dev, size_t size,
  54                                 void *vaddr, dma_addr_t dma_handle);
  55         dma_addr_t      (*map_single)(struct device *dev, void *ptr,
  56                                 size_t size, enum dma_data_direction direction);
  57         void            (*unmap_single)(struct device *dev, dma_addr_t dma_addr,
  58                                 size_t size, enum dma_data_direction direction);
  59         int             (*map_sg)(struct device *dev, struct scatterlist *sg,
  60                                 int nents, enum dma_data_direction direction);
  61         void            (*unmap_sg)(struct device *dev, struct scatterlist *sg,
  62                                 int nents, enum dma_data_direction direction);
  63         int             (*dma_supported)(struct device *dev, u64 mask);
  64         int             (*set_dma_mask)(struct device *dev, u64 dma_mask);
  65 };
  66
  67 static inline struct dma_mapping_ops *get_dma_ops(struct device *dev)
  68 {
  69         /* We don't handle the NULL dev case for ISA for now. We could
  70          * do it via an out of line call but it is not needed for now. The
  71          * only ISA DMA device we support is the floppy and we have a hack
  72          * in the floppy driver directly to get a device for us.
  73          */
  74         if (unlikely(dev == NULL || dev->archdata.dma_ops == NULL))
  75                 return NULL;
  76         return dev->archdata.dma_ops;
  77 }
  78
  79 static inline void set_dma_ops(struct device *dev, struct dma_mapping_ops *ops)
  80 {
  81         dev->archdata.dma_ops = ops;
  82 }
  83
  84 static inline int dma_supported(struct device *dev, u64 mask)
  85 {
  86         struct dma_mapping_ops *dma_ops = get_dma_ops(dev);
  87
  88         if (unlikely(dma_ops == NULL))
  89                 return 0;
  90         if (dma_ops->dma_supported == NULL)
  91                 return 1;
  92         return dma_ops->dma_supported(dev, mask);
  93 }
  94
  95 /* We have our own implementation of pci_set_dma_mask() */
  96 #define HAVE_ARCH_PCI_SET_DMA_MASK
  97
  98 static inline int dma_set_mask(struct device *dev, u64 dma_mask)
  99 {
 100         struct dma_mapping_ops *dma_ops = get_dma_ops(dev);
 101
 102         if (unlikely(dma_ops == NULL))
 103                 return -EIO;
 104         if (dma_ops->set_dma_mask != NULL)
 105                 return dma_ops->set_dma_mask(dev, dma_mask);
 106         if (!dev->dma_mask || !dma_supported(dev, dma_mask))
 107                 return -EIO;
 108         *dev->dma_mask = dma_mask;
 109         return 0;
 110 }
 111
 112 static inline void *dma_alloc_coherent(struct device *dev, size_t size,
 113                                        dma_addr_t *dma_handle, gfp_t flag)
 114 {
 115         struct dma_mapping_ops *dma_ops = get_dma_ops(dev);
 116
 117         BUG_ON(!dma_ops);
 118         return dma_ops->alloc_coherent(dev, size, dma_handle, flag);
 119 }
 120
 121 static inline void dma_free_coherent(struct device *dev, size_t size,
 122                                      void *cpu_addr, dma_addr_t dma_handle)
 123 {
 124         struct dma_mapping_ops *dma_ops = get_dma_ops(dev);
 125
 126         BUG_ON(!dma_ops);
 127         dma_ops->free_coherent(dev, size, cpu_addr, dma_handle);
 128 }
 129
 130 static inline dma_addr_t dma_map_single(struct device *dev, void *cpu_addr,
 131                                         size_t size,
 132                                         enum dma_data_direction direction)
 133 {
 134         struct dma_mapping_ops *dma_ops = get_dma_ops(dev);
 135
 136         BUG_ON(!dma_ops);
 137         return dma_ops->map_single(dev, cpu_addr, size, direction);
 138 }
 139
 140 static inline void dma_unmap_single(struct device *dev, dma_addr_t dma_addr,
 141                                     size_t size,
 142                                     enum dma_data_direction direction)
 143 {
 144         struct dma_mapping_ops *dma_ops = get_dma_ops(dev);
 145
 146         BUG_ON(!dma_ops);
 147         dma_ops->unmap_single(dev, dma_addr, size, direction);
 148 }
 149
 150 static inline dma_addr_t dma_map_page(struct device *dev, struct page *page,
 151                                       unsigned long offset, size_t size,
 152                                       enum dma_data_direction direction)
 153 {
 154         struct dma_mapping_ops *dma_ops = get_dma_ops(dev);
 155
 156         BUG_ON(!dma_ops);
 157         return dma_ops->map_single(dev, page_address(page) + offset, size,
 158                         direction);
 159 }
 160
 161 static inline void dma_unmap_page(struct device *dev, dma_addr_t dma_address,
 162                                   size_t size,
 163                                   enum dma_data_direction direction)
 164 {
 165         struct dma_mapping_ops *dma_ops = get_dma_ops(dev);
 166
 167         BUG_ON(!dma_ops);
 168         dma_ops->unmap_single(dev, dma_address, size, direction);
 169 }
 170
 171 static inline int dma_map_sg(struct device *dev, struct scatterlist *sg,
 172                              int nents, enum dma_data_direction direction)
 173 {
 174         struct dma_mapping_ops *dma_ops = get_dma_ops(dev);
 175
 176         BUG_ON(!dma_ops);
 177         return dma_ops->map_sg(dev, sg, nents, direction);
 178 }
 179
 180 static inline void dma_unmap_sg(struct device *dev, struct scatterlist *sg,
 181                                 int nhwentries,
 182                                 enum dma_data_direction direction)
 183 {
 184         struct dma_mapping_ops *dma_ops = get_dma_ops(dev);
 185
 186         BUG_ON(!dma_ops);
 187         dma_ops->unmap_sg(dev, sg, nhwentries, direction);
 188 }
 189
 190
 191 /*
 192  * Available generic sets of operations
 193  */
 194 extern struct dma_mapping_ops dma_iommu_ops;
 195 extern struct dma_mapping_ops dma_direct_ops;
 196
 197 #else /* CONFIG_PPC64 */
 198
 199 #define dma_supported(dev, mask)        (1)
 200
 201 static inline int dma_set_mask(struct device *dev, u64 dma_mask)
 202 {
 203         if (!dev->dma_mask || !dma_supported(dev, mask))
 204                 return -EIO;
 205
 206         *dev->dma_mask = dma_mask;
 207
 208         return 0;
 209 }
 210
 211 static inline void *dma_alloc_coherent(struct device *dev, size_t size,
 212                                        dma_addr_t * dma_handle,
 213                                        gfp_t gfp)
 214 {
 215 #ifdef CONFIG_NOT_COHERENT_CACHE
 216         return __dma_alloc_coherent(size, dma_handle, gfp);
 217 #else
 218         void *ret;
 219         /* ignore region specifiers */
 220         gfp &= ~(__GFP_DMA | __GFP_HIGHMEM);
 221
 222         if (dev == NULL || dev->coherent_dma_mask < 0xffffffff)
 223                 gfp |= GFP_DMA;
 224
 225         ret = (void *)__get_free_pages(gfp, get_order(size));
 226
 227         if (ret != NULL) {
 228                 memset(ret, 0, size);
 229                 *dma_handle = virt_to_bus(ret);
 230         }
 231
 232         return ret;
 233 #endif
 234 }
 235
 236 static inline void
 237 dma_free_coherent(struct device *dev, size_t size, void *vaddr,
 238                   dma_addr_t dma_handle)
 239 {
 240 #ifdef CONFIG_NOT_COHERENT_CACHE
 241         __dma_free_coherent(size, vaddr);
 242 #else
 243         free_pages((unsigned long)vaddr, get_order(size));
 244 #endif
 245 }
 246
 247 static inline dma_addr_t
 248 dma_map_single(struct device *dev, void *ptr, size_t size,
 249                enum dma_data_direction direction)
 250 {
 251         BUG_ON(direction == DMA_NONE);
 252
 253         __dma_sync(ptr, size, direction);
 254
 255         return virt_to_bus(ptr);
 256 }
 257
 258 static inline void dma_unmap_single(struct device *dev, dma_addr_t dma_addr,
 259                                     size_t size,
 260                                     enum dma_data_direction direction)
 261 {
 262         /* We do nothing. */
 263 }
 264
 265 static inline dma_addr_t
 266 dma_map_page(struct device *dev, struct page *page,
 267              unsigned long offset, size_t size,
 268              enum dma_data_direction direction)
 269 {
 270         BUG_ON(direction == DMA_NONE);
 271
 272         __dma_sync_page(page, offset, size, direction);
 273
 274         return page_to_bus(page) + offset;
 275 }
 276
 277 static inline void dma_unmap_page(struct device *dev, dma_addr_t dma_address,
 278                                   size_t size,
 279                                   enum dma_data_direction direction)
 280 {
 281         /* We do nothing. */
 282 }
 283
 284 static inline int
 285 dma_map_sg(struct device *dev, struct scatterlist *sgl, int nents,
 286            enum dma_data_direction direction)
 287 {
 288         struct scatterlist *sg;
 289         int i;
 290
 291         BUG_ON(direction == DMA_NONE);
 292
 293         for_each_sg(sgl, sg, nents, i) {
 294                 BUG_ON(!sg_page(sg));
 295                 __dma_sync_page(sg_page(sg), sg->offset, sg->length, direction);
 296                 sg->dma_address = page_to_bus(sg_page(sg)) + sg->offset;
 297         }
 298
 299         return nents;
 300 }
 301
 302 static inline void dma_unmap_sg(struct device *dev, struct scatterlist *sg,
 303                                 int nhwentries,
 304                                 enum dma_data_direction direction)
 305 {
 306         /* We don't do anything here. */
 307 }
 308
 309 #endif /* CONFIG_PPC64 */
 310
 311 static inline void dma_sync_single_for_cpu(struct device *dev,
 312                 dma_addr_t dma_handle, size_t size,
 313                 enum dma_data_direction direction)
 314 {
 315         BUG_ON(direction == DMA_NONE);
 316         __dma_sync(bus_to_virt(dma_handle), size, direction);
 317 }
 318
 319 static inline void dma_sync_single_for_device(struct device *dev,
 320                 dma_addr_t dma_handle, size_t size,
 321                 enum dma_data_direction direction)
 322 {
 323         BUG_ON(direction == DMA_NONE);
 324         __dma_sync(bus_to_virt(dma_handle), size, direction);
 325 }
 326
 327 static inline void dma_sync_sg_for_cpu(struct device *dev,
 328                 struct scatterlist *sgl, int nents,
 329                 enum dma_data_direction direction)
 330 {
 331         struct scatterlist *sg;
 332         int i;
 333
 334         BUG_ON(direction == DMA_NONE);
 335
 336         for_each_sg(sgl, sg, nents, i)
 337                 __dma_sync_page(sg_page(sg), sg->offset, sg->length, direction);
 338 }
 339
 340 static inline void dma_sync_sg_for_device(struct device *dev,
 341                 struct scatterlist *sgl, int nents,
 342                 enum dma_data_direction direction)
 343 {
 344         struct scatterlist *sg;
 345         int i;
 346
 347         BUG_ON(direction == DMA_NONE);
 348
 349         for_each_sg(sgl, sg, nents, i)
 350                 __dma_sync_page(sg_page(sg), sg->offset, sg->length, direction);
 351 }
 352
 353 static inline int dma_mapping_error(dma_addr_t dma_addr)
 354 {
 355 #ifdef CONFIG_PPC64
 356         return (dma_addr == DMA_ERROR_CODE);
 357 #else
 358         return 0;
 359 #endif
 360 }
 361
 362 #define dma_alloc_noncoherent(d, s, h, f) dma_alloc_coherent(d, s, h, f)
 363 #define dma_free_noncoherent(d, s, v, h) dma_free_coherent(d, s, v, h)
 364 #ifdef CONFIG_NOT_COHERENT_CACHE
 365 #define dma_is_consistent(d, h) (0)
 366 #else
 367 #define dma_is_consistent(d, h) (1)
 368 #endif
 369
 370 static inline int dma_get_cache_alignment(void)
 371 {
 372 #ifdef CONFIG_PPC64
 373         /* no easy way to get cache size on all processors, so return
 374          * the maximum possible, to be safe */
 375         return (1 << INTERNODE_CACHE_SHIFT);
 376 #else
 377         /*
 378          * Each processor family will define its own L1_CACHE_SHIFT,
 379          * L1_CACHE_BYTES wraps to this, so this is always safe.
 380          */
 381         return L1_CACHE_BYTES;
 382 #endif
 383 }
 384
 385 static inline void dma_sync_single_range_for_cpu(struct device *dev,
 386                 dma_addr_t dma_handle, unsigned long offset, size_t size,
 387                 enum dma_data_direction direction)
 388 {
 389         /* just sync everything for now */
 390         dma_sync_single_for_cpu(dev, dma_handle, offset + size, direction);
 391 }
 392
 393 static inline void dma_sync_single_range_for_device(struct device *dev,
 394                 dma_addr_t dma_handle, unsigned long offset, size_t size,
 395                 enum dma_data_direction direction)
 396 {
 397         /* just sync everything for now */
 398         dma_sync_single_for_device(dev, dma_handle, offset + size, direction);
 399 }
 400
 401 static inline void dma_cache_sync(struct device *dev, void *vaddr, size_t size,
 402                 enum dma_data_direction direction)
 403 {
 404         BUG_ON(direction == DMA_NONE);
 405         __dma_sync(vaddr, size, (int)direction);
 406 }
 407
 408 #endif /* __KERNEL__ */
 409 #endif  /* _ASM_DMA_MAPPING_H */